package com.example.springboot.common.utils;

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.UUID;

public class UUIDGenerator {

	public static String[] chars = new String[] { "a", "b", "c", "d", "e", "f",
			"g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s",
			"t", "u", "v", "w", "x", "y", "z", "0", "1", "2", "3", "4", "5",
			"6", "7", "8", "9", "A", "B", "C", "D", "E", "F", "G", "H", "I",
			"J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V",
			"W", "X", "Y", "Z" };

	/**
	 * 创建主键ID
	 * @return	返回格式:"yyyyMMddHHmmss"+8位UUID字符
	 */
	public static String generateId() {

		Date now = new Date();
		DateFormat format = new SimpleDateFormat("yyyyMMddHHmmss");

		String id = format.format(now) + generateShortUuid();
		return id;
	}

	public static String generateShortUuid() {
		StringBuffer shortBuffer = new StringBuffer();
		String uuid = UUID.randomUUID().toString().replace("-", "");
		for (int i = 0; i < 8; i++) {
			String str = uuid.substring(i * 4, i * 4 + 4);
			int x = Integer.parseInt(str, 16);
			shortBuffer.append(chars[x % 0x3E]);
		}
		return shortBuffer.toString();
	}

	/**
	 * 生成UUID字符串
	 * 如果需要产生主键请使用{@link #generateId()} generateId()
	 *
	 * 例如:2cda7135b9f0416b980a00110ff38d86
	 * @return UUID字符串
	 */
	public static String getUUID() {
		String str = UUID.randomUUID().toString();
		return str.substring(0, 8) + str.substring(9, 13) + str.substring(14, 18) + str.substring(19, 23) + str.substring(24);
	}

	public static String[] getUUID(int paramInt) {
		if (paramInt < 1) {
			return null;
		}
		String[] arrayOfString = new String[paramInt];
		for (int i = 0; i < paramInt; i++) {
			arrayOfString[i] = getUUID();
		}
		return arrayOfString;
	}

	public static void main(String[] paramArrayOfString) {
		String[] arrayOfString = UUID.randomUUID().toString().split("-");
		for (String element : arrayOfString) {
			System.out.println("ok:" + element);
			long l = Long.valueOf(element, 16).longValue();
			System.out.println("ok:===" + l);
		}
	}

	/**
	 * 创建主键ID
	 *
	 * @return 返回格式:"yyyyMMddHHmmss"+ appendString +8位UUID字符
	 */
	public static String generateAppendStrId(String appendString) {

		Date now = new Date();
		DateFormat format = new SimpleDateFormat("yyyyMMddHHmmss");

		String id = format.format(now) + appendString + generateShortUuid();
		return id;
	}
}